In testing, eROT recovered an average of 100 to 150 watts on a typical German road, three watts from a fresh piece of pavement, and 613 watts on a rough stretch of tarmac (wattage is calculated as power over time, so this is actually the rate at which the system harvests energy). The dampers channel that energy to a tiny, 0.5-kWh, 48-volt battery. The prototype is claimed to cut CO2 emissions by three grams per kilometer (4.8 grams per mile), while the company believes a future production version could save up to 0.7 liters of fuel per 100 kilometers of driving.

There are a few other big benefits beyond fuel and emissions savings – Audi claims eROT provides a more comfortable ride than traditional active suspensions, because engineers can tune the compression and rebound strokes independently of each other. Beyond that, the horizontally oriented rear suspension geometry means more cargo space, since the dampers don’t poke up into the cabin like they normally do.

eROT is still firmly in the prototype stage, but Audi claims a production is “certainly plausible” thanks to its promising test results. The company is preparing a new version for 2017, where it will appear on a 48-volt vehicle to “feed a high performance mild hybrid drive.

A suspension system that can use poor roads to improve fuel economy is innovative, with a potential fuel saving of 0.7L/100km being very significant. If used across Audi's entire production car range, the environmental benefits could be huge. Together with other technologies such as regenerative braking, could a future iteration of this suspension be used to also power the electrical systems of the car itself, such as lighting and infotainment?

For the Australian consumer, the reduced fuel consumption could reduce car prices, with models having a combined fuel consumption under 7.0L/100km having a higher threshold for the Luxury Car Tax (LCT).